北三河流域洪水资源量的演变特性及驱动因素评估

Evolution properties and driving factors of flood resources quantity in Beisanhe basin

初步提出了洪水资源和洪水资源量的定义，利用Mann—Kendall、Spearman两种非参数统计方法和Morlet连续小波分析揭示了海河水系北三河流域洪水资源量的演变特征．根据分阶段降水量-洪水资源量关系，评估了降水和其它驱动因素对该流域洪水资源量变化的影响程度．研究结果表明，1956～2000年间，北三河流域洪水资源量具有显著的衰减趋势，呈现出以17年、9年和4年为准周期的多时间尺度丰枯振荡，1979年是45年来洪水资源量丰枯变异最显著的转折点．降水变化对北三河流域洪水资源量变化起主导作用，对于全流域，1959～1979年和1980～2000年两阶段相比，降水和非降水因素对洪水资源量减少的相对影响程度分别为70．5％和29．5％，对于山区分别为75．5％和24．5％，在平原区，非降水因素对洪水资源量变化的影响甚小．

The conceptions of flood resources and flood resources quantity are proposed in this paper. Then, evolution properties of flood resources quantity in Beisanhe basin, a sub basin of Haihe basin, are comprehensively investigated by Mann-Kendall, Spearman nonparametric testing and Morlet continuous wavelet analysis. Meanwhile, by empirical formulas between annual rainfall and flood resources quantity during different phases, the influence of precipitation and other driving factors on flood resources change are investigated and evaluated. The results show that the decay tendency of flood resources quantity in Beisanhe basin is remarkable from 1956 to 2000, and that the most distinct changing point of flood resources quantity is in 1979. The flood resources quantity series has a complicated oscillation with approximate periodicals of 17, 14 and 4 years. Precipitation is the dominant driving factor of flood resources quantity change. During the two periods of 1959 - 1979 and 1980 - 2000, in the whole basin, the effects of precipitation and other factors on flood resources quantity change are 70. 5% and 29.5%. For the mountainous region, corresponding values are 75.5% and 24.5% respectively. For the plain region, the effects of other factors are very weak compared with precipitation change.